Need help ! if you can pls try to explain how you got your answer step by step :)

the correct is answer is a 9-sided polygon!

by definition, an arc subtended by a central angle of some given measure has the same measure. so .

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!